The acoustic impact testing method is presented with two different excitation methods: the tap testing method and the acoustic impedance testing method.The tap testing method includes the whole vibration testing(wheel-tap test) method and the local vibration testing method(coin-tap test),and the acoustic impedance method has the mechanical impedance method and the local resonance testing method.Though the acoustic impact testing method has a long history in testing activities,most concerns of this method are only restricted in its experiential applications.Here,the principals and their developments of several branches of the acoustic impact testing method are covered,with the main purpose to improve this old but effective method with the help of the people who concern its development and applications.

Conventional ultrasonic NDT method is quite incompetence for the surface fatigue crack testing of in service rotary shaft Considering the formation mechanism of the surface fatigue crack in rotary shaft and the propagation character of ultrasonic creeping wave in media,ultrasonic creeping wave was employed to the surface fatigue crack detection of in service rotary shaft. An experiment was carried out on a certain type of stepped rotary shaft for the testing of surface fatigue cracks. The result revealed that,this method was simple and efficient for the surface fatigue crack testing of in service rotary shaft,and it could be applied for the routine testing of in service rotary shaft.

为了全面提高检测效率、实时性和可靠性,利用现代超声检测技术、计算机技术、电子技术、信号处理技术等研制出一种多通道超声检测仪.介绍了该仪器的硬件和软件设计方法.实验结果表明:通道间的一致性非常好,发射接收系统性能优越,四通道探伤时每通道最高重复频率可达10kHz,基于FPGA的设计使得设备可方便满足各种用户和环境的需求.